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Introduction: Allan Hills 84001 (ALH 84001) is an orthopyroxenite Martian meteorite containing coarse-grained inclusions of chromites, carbonates and plagioclase feldspar, in addition to fine-grained iron oxides and sulfides that host a heterogeneously oriented natural remanent magnetization (NRM) [1]-[4]. The meteorite contains several shockinduced textures and mineral thermometers indicative of one or more impact events. The NRM hosted in the iron oxides and chromite-sulfide assemblages within the meteorite is understood to be a thermoremanent magnetization (TRM) and has two strongly magnetized components that do not share common alignment, in addition to several incoherent, weakly magnetized grains, indicative of an underlying mechanism capable of localized (~200 nm) heating [5]. We have developed a methodology, using thermal constraints from paleomagnetism and petrologic observation, where we are able to place new constraints on the shock pressures associated with multiple impacts suffered by the meteorite up to and including its ejection from Mars. To reconcile the reported thermal histories of the meteorite, we have simulated planar shock wave propagation through computational analogs of two samples of ALH 84001. Modeling: Using the iSALE-2D shock physics code [6]-[8], we have performed a suite of 'mesoscale' simulations to quantify the effects of impact-induced shockwaves likely to have been experienced by the meteorite. The materials used in our simulations are each described by an equation of state and strength model. As the availability of accurate equations of state for meteoritic materials is limited, we have used the closest analog materials possible. Results: We found strong and complex material shear responsible for steep thermal gradients throughout the sample. Shearing occurs principally in the rock matrix, using the (weaker) inclusions as nucleation points (Fig. 1). We see both intraand inter-material variations in temperature on length scales of tens of microns. Subsequent modeling of post-impact thermal equilibration reveals that the constituent materials reach equilibrium ~3 seconds after the release wave has passed through the meteorite (Fig. 1). This has implications for paleomagnetism: small fractions of the meteorite may be remagnetized in low-pressure impacts, meaning the meteorite is capable of hosting NRMs recorded at different times. Implications for Paleomagnetism: Palaeomagnetic studies of this meteorite have found a heterogeneously oriented pattern of remanent magnetization, indicative of remagnetization in the meteorite on the sub-millimeter scale, but the mechanism for such heterogeneous heating was unclear. We observe that portions of chromite grains close to shear zones will experience temperatures significantly higher than those elsewhere in the meteorite which only warm up to the equilibrium temperature. Since the meteorite was magnetized in an initial extensive thermal event where the whole meteorite was heated above the curie point of the chromite-sulfide assemblages, our simulations suggest that a subsequent impact with a bulk shock pressure between 25-45 GPa would achieve partial remagnetization. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To study the impact of the Risk-Scoring Tool (RST) as a strategy for targeting prophylaxis effectively in 33-35-week gestational age (GA) Canadian infants who range from low to high risk by evaluating the subsequent incidence of respiratory syncytial virus (RSV) infections resulting in emergency room (ER) visits and hospitalization. DESIGN: Prospective, descriptive study. SETTING: McMaster Children's Hospital and St Joseph's Healthcare in Hamilton, Ontario. PARTICIPANTS: Premature infants between 33 and 35 weeks' completed gestation who were less than 6 months' chronological age at the start of, or during, the local 2005-2008 RSV winter seasons. METHODS: A validated, Canadian RST was used to calculate a total risk score based on seven risk factors. Only infants at moderate (RST score 49-64) and high risk (RST score 65-100) received palivizumab at monthly intervals from November to April and were followed during the respective RSV seasons. All parents received information on RSV prevention at hospital discharge. Parents of all recruited infants were contacted by telephone in May at the end of each season, and medical records were checked to determine ER visits for RSV-related respiratory tract infections and RSV hospitalization. Means, standard deviations, ranges, and percents were used to describe the variables for patients enrolled in the study. RESULTS: Over 3 years, 430 infants were recruited. Of these, 346 (81%), 57 (13%), and 27 (6%) were in the low-, moderate- and high-risk categories, respectively, based on their risk scores. A total of 78 (18.1%) infants received full courses of palivizumab. Six out of 57 (10.5%) infants in the moderate-risk group did not receive prophylaxis, while all 27 high-risk group infants received palivizumab. Seven (1.6%) infants were RSV-positive and five (low-risk) infants were hospitalized. One high-risk, RSV-positive infant, was seen in the ER, and discharged home. There were no statistical differences in the number of infants with RSV-related ER visits and hospitalizations within the risk category groups (p = 0.43). The limitations of this study include the observational design and the relatively small sample size. CONCLUSIONS: The RST is a practical, easy-to-use instrument to guide judicious RSV prophylaxis for moderate-high-risk, 33-35-week GA infants. It is cost-effective, reducing hospitalization in infants who are most 'at-risk', while avoiding prophylaxis in a large segment (81.9%) of this GA cohort who are considered low risk for RSV infection. [ABSTRACT FROM AUTHOR]

Injection of antisense oligonucleotide morpholinos to elicit selective gene knockdown of ammonia (Rhag, Rhbg, and Rhcg1) or urea transporters (UT) was used as a tool to assess the relative importance of each transporter to nitrogen excretion in developing zebrafish (Danio rerio). Knockdown of UT caused urea excretion to decrease by ∼90%, whereas each of the Rh protein knockdowns resulted in an ∼50% reduction in ammonia excretion. Contrary to what has been hypothesized previously for adult fish, each of the Rh proteins appeared to have a similar effect on total ammonia excretion, and thus all are required to facilitate normal ammonia excretion in the zebrafish larva. As demonstrated in other teleosts, zebrafish embryos utilized urea to a much greater extent than adults and were effectively ureotelic until hatching. At that point, ammonia excretion rapidly increased and appeared to be triggered by a large increase in the mRNA expression of Rhag, Rhbg, and Rhcg1. Unlike the situation in the adult pufferfish (35), the various transporters are not specifically localized to the gills of the developing zebrafish, but each protein has a unique expression pattern along the skin, gills, and yolk sac. This disparate pattern of expression would appear to preclude interaction between the Rh proteins in zebrafish embryos. However, this mily be a developmental feature of the delayed maturation of the gills, because as the embryos matured, expression of the transporters in and around the gills increased. [ABSTRACT FROM AUTHOR]

Objective: To identify outcomes and prognostic variables that predict survival outcomes in adult Wilms tumour patients. Methods: We collected data on 128 patients with adult Wilms tumour treated between 1973 and 2006. Six cases from our 2 Canadian centres have not been previously reported. We collected data on the remaining 122 patients from published case reports or case series. Analyzed factors included age, sex, favourable or unfavourable histopathology, clinical stage (I, II, III or IV) and chemotherapy and radiotherapy received. The outcomes studied included overall survival (OS) and disease-specific survival (DSS). Univariate analysis with KaplanDSMeier actuarial methodology and multivariate analyses with Cox regression were used to determine outcomes and predictive clinical factors. Results: The patients' mean age was 26 (range 15DS73) years. After a mean follow-up of 54 (range 2DS240) months, the OS and DSS of the entire cohort were both 68%. Favourable histopathology predicted superior OS and DSS (both p < 0.001). Higher clinical stage predicted inferior OS and DSS (both p < 0.001). Conclusion: Adult Wilms tumour has a poorer prognosis than pediatric Wilms tumour. In adults with Wilms tumour, more aggressive patient- and tumour-specific surveillance and adjunctive therapies than those advocated by pediatric National Wilms Tumor Study guidelines may be warranted, especially in patients with an unfavourable histopathology and higher clinical stage. [ABSTRACT FROM AUTHOR]

Objective: For a variety of reasons, many emergency department (ED) visits are classified as less- or nonurgent (Canadian Triage and Acuity Scale [CTAS] level IV and V). A recent survey in a tertiary care ED identified some of these reasons. The purpose of our study was to determine if these same reasons applied to patients presenting with problems triaged at a similar level at a lowvolume rural ED. Methods: A 9-question survey tool was administered to 141 CTAS level IV and V patients who attended the South Huron Hospital ED, in Exeter, Ontario, over a 2-week period in December 2006. Results: Of the 141 eligible patients, 137 (97.2%) completed the study. One hundred and twenty-two patients (89.1%) reported having a family physician (FP) and 53 (38.7%) had already seen an FP before presenting to the ED. Just over one-half of all patients (51.1%) had their problem for more than 48 hours, and 42 (30.7%) stated that they were referred to the ED for care. Fifty-three (38.7%) of the respondents felt they needed treatment as soon as possible. Many patients reported coming to the ED because: 1) their FP office was closed (21.9%); 2) they could not get a timely appointment (16.8%); or 3) the walk-in clinic was closed (24.8%). Only 6 patients (4.4%) specifically stated that they came to the ED because they had no FP. One-third of patients attended the ED because they believed it offered specialized services. Conclusion: In this rural setting, most less- or nonurgent ED patients had an FP yet they went to the ED because they did not have access to primary care, because they perceived their problem to be urgent or because they were referred for or sought specific services. [ABSTRACT FROM AUTHOR]

From 1985 to 1992, Michele was consultant veterinarian to Riyadh Municipality zoo, responsible for the health of over 500 zoo animals, marine mammals and bird species. Michele and her family returned to Sydney in 1999 due to her husband's diagnosis with mesothelioma. Michele is survived by her children and their partners Andrei and Kelli, Sofia and Nathan and Peter and her grandchildren Roman and Elena. [Extracted from the article]

OBJECTIVE: To assess the association of cognitive dysfunction and depression with serum antibodies to N-methyl-D-aspartate (NMDA) receptor (anti-NR2) and analyze clinical and neuroimaging correlates in patients with systemic lupus erythematosus (SLE). METHODS: Sixty patients underwent neurocognitive assessment, evaluation for depression with the Beck Depression Inventory II (BDI-II) and psychiatric interview (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition [DSM-IV] criteria), brain magnetic resonance imaging, and proton magnetic resonance spectroscopy imaging ((1)H-MRSI). Cognition was assessed in 5 domains: memory, attention/executive, visuospatial, motor, and psychomotor, and adjusted to each individual's best level of prior cognitive functioning estimated from the reading subtest of the Wide Range Achievement Test-3 (WRAT-3). Serum anti-NR2 antibodies were measured by enzyme-linked immunosorbent assay using a pentapeptide from the human NMDA receptor. RESULTS: Cognitive dysfunction was found in 28 of 60 patients (mild in 8, moderate in 20) before adjustment for WRAT-3 and in 35 of 60 patients (mild in 15, moderate in 11, and severe in 9) after adjustment for WRAT-3. The changes were most pronounced in the memory and visuospatial domains. There was no significant association between anti-NR2 antibody levels and cognition. On (1)H-MRSI, patients with moderate or severe cognitive dysfunction had significantly higher choline:creatine ratios in the dorsolateral prefrontal cortex and the white matter, compared with patients with mild or absent cognitive dysfunction. Anti-NR2 antibodies were significantly correlated with BDI scores; patients with BDI-II scores of >/=14 had higher serum levels of anti-NR2 antibodies (P = 0.005, 95% confidence interval 0.83, 4.31), and there was a trend toward higher anti-NR2 antibody levels among patients who fulfilled the DSM-IV criteria for major depression. CONCLUSION: Serum anti-NR2 antibodies are associated with depressive mood but not with cognitive dysfunction in SLE at a given time point. Larger longitudinal studies are needed to address the possible association between anti-NR2 antibodies and depression in SLE. [ABSTRACT FROM AUTHOR]

Marine elasmobranchs retain relatively high levels of urea to counterbalance the osmotic strength of seawater. Oviparous species, such as the little skate Raja erinacea, release encapsulated embryos that hatch after about 9 months on the seafloor. To study the ureosmotic capability of skate embryos, we measured a variety of possible osmolytes and ornithine-urea cycle (OUC) enzyme activities in little skate embryos, and determined their physiological response to dilute seawater (75% SW) exposure relative to controls (100% SW). The urea:trimethylamine oxide (TMAO) + other osmolytes ratio was 2.3–2.7:1. At the earliest stage of development investigated (4 months), there were significant levels of the key OUC enzyme, carbamoyl phosphate synthetase III, as well as ornithine transcarbamoylase, arginase and glutamine synthetase, providing evidence for a functional 0UC. Embryos (4 and 8 months) survived and recovered from exposure to 5 days of 75% SW. There was a significant increase in the rate of urea excretion (five- to tenfold), no change in OUC enzyme activities, and significant decreases in the tissue content of urea, TMAO and other osmolytes in embryos exposed to 75% SW compared to 100% SW. Taken together, the data indicate that little skate embryos synthesize and retain urea, as well as a suite of other osmolytes, in order to regulate osmotic balance with the external environment. Interestingly, these ureosmotic mechanisms are in place as early as 4 months, around the time at which the egg capsule opens and the embryo is in more direct contact with the external environment. [ABSTRACT FROM AUTHOR]

This longitudinal study investigated developmental change in theory of mind among 57 children with autism aged between 4 to 14 years at the start of the study. On an initial visit and one year later, each participant was administered a battery of tests designed to measure a broad developmental range of theory of mind abilities from early (e.g., desire) to more advanced (e.g., moral judgment) mental state understanding. Both group and individual data indicated significant developmental improvement in theory of mind ability, which was primarily related to the children's language abilities. [ABSTRACT FROM AUTHOR]

Since nurses hold a unique perspective and pivotal role in health care delivery, they have the opportunity to have a notable impact on policy through their nearly 2.7 million voices.Patient and professional advocacy are clearly needed now with such vivid threats to health care delivery as patient safety and RN scarcity.The Policy Analysis Model (PAM) is described as a cognitive framework for health policy analysis.The PAM was developed as a tool for nurse managers to wrestle with emerging policy issues through the identification of various forces at play.The steps in the PAM include identification of: problems; social factors; financial ethical/legal, and political constraints; and policy alternatives, objectives, and evaluation of options.Nurse managers can utilize this framework as a way to educate and involve their staff as a vehicle for individual professional development, as well as local, regional, or national change.Several policy Web sites are offered as resources for identifying issues affecting nursing. [ABSTRACT FROM AUTHOR]

Ripley's stage sequential model is used to analyze the disparity in the Medicare reimbursement for screening mammography for older women in the United States. The article presents a historical review of the policy issue and suggests solutions to set the agenda for policy change. Problem identification, costs, and ethical and social issues are evaluated, and policy change is recommended. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Incomplete mesorectal excision during rectal cancer surgery often leads to positive circumferential margins, with uncertain prognostic impacts. This study examines whether negative margins can mitigate the poorer prognosis typically associated with incomplete total mesorectal excision (TME) in rectal cancer surgery, thus potentially challenging the prevailing emphasis on complete mesorectal excision. Patients and methods: A retrospective analysis was conducted on patients who underwent proctectomy for rectal adenocarcinoma with incomplete TME at a single center from 2010 to 2022. Patients were stratified by margin status as determined by pathologic analysis into three groups: involved, not involved with closest margin distance ≤ 2 mm, and not involved with closest margin distance > 2 mm. Outcomes included recurrence and survival. Effects of neoadjuvant therapy protocols on margin status were also assessed. Results: From 2010 to 2022, 7941 patients underwent proctectomy for rectal cancer, with 236 (3%) having incomplete TME. The median age of these patients was 64 years, and 63% were male. Overall, margin involvement was observed in 54 (23%) patients. The median tumor size was 3.05 cm (interquartile range (IQR): 2–6) for the whole group. Involved margins (23.2%) had reduced overall survival (60.5 months versus 87.3 months, p < 0.001), increased local recurrence (20.4% versus 9.4%, p = 0.024), and lower disease-free survival (45.2 versus 58.9 months, p = 0.006) versus uninvolved margins. Margin involvement was prognostic for decreased survival even after adjusting for confounders (p < 0.05). Among uninvolved margins, distance (> 2 mm versus ≤ 2 mm) did not affect outcomes. Total neoadjuvant therapy (versus standard chemoradiation) was associated with lower involved margins (p = 0.007). Conclusions: Positive margins retain negative prognostic impact with incomplete TME. Optimization of surgical resection remains vital. Total neoadjuvant therapy was associated with a lower rate of margin involvement. [ABSTRACT FROM AUTHOR]

Particle bombardment has been used to transform three cultivars (L35, Ofanto, Svevo) and one breeding line (Latino × Lira) of durum wheat (Triticum turgidum L. var. durum). These varieties were co-transformed with plasmids containing selectable and scorable marker genes (bar and uidA) and plasmids containing one of two high-molecular-weight (HMW) glutenin subunit genes (encoding subunits 1Ax1 or 1Dx5). Ten independent transgenic lines were recovered from 1683 bombarded scutella (transformation efficiency thus 0.6%). Five lines expressed either subunit 1Dx5 or 1Ax1 at levels similar to those of endogenous subunits encoded on chromosome 1B. To identify the effects of the transgenes on the functional properties of grain, three lines showing segregation for transgene expression were used to isolate sibling T2 plants which were null or positive for the transgene product. Analysis of these plants using a small-scale mixograph showed that expression of the additional subunits resulted in increased dough strength and stability, demonstrating that transformation can be used to modify the quality of durum wheat for bread and pasta making. [ABSTRACT FROM AUTHOR]

The high-molecular-weight (HMW) subunits of wheat glutenin are the major determinants of the gluten visco-elasticity that allows wheat doughs to be used to make bread, pasta and other food products. In order to increase the proportions of the HMW subunits, and hence improve breadmaking performance, particle bombardment was used to transform tritordeum, a fertile amphiploid between wild barley and pasta wheat, with genes encoding two HMW glutenin subunits (1Ax1 and 1Dx5). Of the 13 independent transgenic lines recovered (a transformation frequency of 1.4%) six express the novel HMW subunits at levels similar to, or higher than, those of the endogenous subunits encoded on chromosome 1B. Small-scale mixograph analysis of T2 seeds from a line expressing the transgene for 1Dx5 indicated that the addition of novel HMW subunits can result in significant improvements in dough strength and stability, thus demonstrating that transformation can be used to modify the functional properties of tritordeum for improved breadmaking. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fifty-eight somatic hybrid plants, produced both by chemical (11) and electrical fusion (47) of protoplasts of dihaploid Solanum tuberosum and S. brevidens, have been analysed by molecular, cytological and morphological methods. The potentially useful euploid plants constituted 34% of the total, of which 20% were tetraploid and 14% hexaploid; the remainder were aneuploid at the tetraploid, hexaploid and octoploid levels. Analysis of chloroplast DNA showed that 55% of hybrids contained chloroplasts from S. brevidens and 45% from S. tuberosum. Hexaploids, the products of three protoplasts fusing together, were analyzed with specific DNA probes, and this revealed that nuclear genome dosages could be either 2∶1 S. tuberosum∶S. brevidens, or vice-versa. Chloroplast types of hexaploids were not influenced by nuclear genome dosage, and all six possible combinations of genome dosage and chloroplast types were found amongst tetraploids and hexaploids. To examine the morphology of the hybrid population and its possible relation to the chromosome number and chloroplast DNA type, 18 morphological characteristics were measured on greenhouse-grown plants and analyzed by principal component and canonical variate analyses. Both analyses showed that nuclear ploidy has the most prominent influence on the overall morphology of the hybrids. Differential parental genome expression in the morphology of the hybrids is discussed. These results provide useful data on the range of genetic combinations that can be expected to occur amongst somatic hybrid plants. [ABSTRACT FROM AUTHOR]